1. Field of the Invention
This invention relates to a firefly enzyme luciferase gene, a firefly enzyme, a recombinant vector containing the gene and a bacterium containing the recombinant vector.
2. Description of the Related Art
The firefly luciferase catalyzes a reaction forming oxyluciferin, CO.sub.2, AMP and pyrophosphoric acid, through D-luciferin as a luminescent substrate, in the presence of ATP, O.sub.2 and Mg.sup.2+. As a result of this reaction, it has been known to emit a light of 560 nm. Luciferase has been used for determining ATP from old time, by utilizing the above ATP-dependent reaction.
de Wet et al isolated luciferase c DNA from Photinus pyralis (de Wet, J. R., K. V. Wood, D. R. Helinski and M. Deluca, 1985, Proc. Natl. Acad. Sci. U.S.A. 82, 7870-7873). Further, de Wet et al isolated genomic DNA thereof and decided the nucleotide sequence of a gene corresponding to luciferase (de Wet, J. R., K. V. Wood, M. DeLuca, D. R. Helinski and S. Subramani, 1987, Mol. Cell. Biol. 7, 725-737).
Masuda et al cloned the luciferase cDNA of Luciola cruciata and determined its nucleotide sequence (Masuda, T., H. Tatsumi and E. Nakano, 1989. Gene 77, 265-270. Tatsumi et al cloned the luciferase cDNA of Luciola lateralis and determined its nucleotide sequence (Tatsumi et al, H., N. Kajiyama and E. Nakano, 1992, Biochim. Biophys. Acta 1131 161-165).
Further, Wood et al isolated luciferase cDNAs originated from Pyrophorus plagiophthalamus and determined its nucleotide sequence (Wood, K. V., Y. A. Lam, H. H. Seliger and W. D. McElroy, 1989, Science 244 700-702).
Recently, utilizing the luminescence reaction of luciferase, measurement of the number of bacterial cells, immunoassay and development of clinical inspection chemicals according to DNA probe method have been attempted. The luciferin.multidot.luciferase reaction can be measured and detected simply, rapidly and with a good sensitivity by means of a luminescence-measuring instrument. Further, using the luciferase gene as a reporter, the quantity of gene expressed and the site of gene expressed have come to be examined.